Vaccines and autism: Many hypotheses, but no correlation

An extensive new review summarizes the many studies refuting the claim of a link between vaccines and autism. The review, in the February 15, 2009 issue of Clinical Infectious Diseases and now available online, looks at the three main hypotheses and shows how epidemiological and biological studies refute these claims.

"When one hypothesis of how vaccines cause autism is refuted, another invariably springs up to take its place," said study author Paul Offit, MD, of the Children's Hospital of Philadelphia. Fears about vaccines are pushing down immunization rates and having a real impact on public health, he added. Vaccine refusal is contributing to the current increase in Haemophilus influenzae cases in Minnesota—including the death of one child—and was a factor in last year's measles outbreak in California.

The controversy began with a 1998 study in The Lancet that suggested a link between the combination measles-mumps-rubella (MMR) vaccine and autism. Dr. Offit and co-author Jeffrey Gerber, MD, PhD, also of the Children's Hospital of Philadelphia, reviewed more than a dozen large studies, conducted in five different countries, that used different methods to address the issue, and concluded that no data supported the association between the MMR vaccine and autism. The correlation between MMR vaccine and the appearance of autism symptoms is merely coincidental, the authors say, because the MMR vaccine is given at the age when autism symptoms usually appear.

Also hypothesized as a cause has been the ethylmercury-containing preservative thimerosal, which was used in vaccines for over 50 years. However, the authors review seven studies from five countries that show that the presence or absence of thimerosal in vaccines did not affect autism rates.

The third suggestion has been that the simultaneous administration of multiple vaccines overwhelms or weakens the immune system. The authors explain that children's immune systems routinely handle much more than the relatively small amount of material contained in vaccines. Furthermore, today's vaccines contain many fewer immune-triggering components than those from decades past. Regardless, autism is not triggered by an immune response, the authors say.

With outbreaks of vaccine-preventable diseases on the rise due to some worried parents choosing not to vaccinate their children, Dr. Offit said, "Parents should realize that a choice not to get a vaccine is not a risk-free choice. It's just a choice to take a different, and far more serious, risk."

Source: Infectious Diseases Society of America

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Citation: Vaccines and autism: Many hypotheses, but no correlation (2009, January 30) retrieved 15 September 2019 from
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Jan 30, 2009
Yarr. When will people get it through their fat heads that many (most) cases of autism are genetic. Parents are just wildly searching for anyone but themselves and their own faulty genes to blame for the specialized type of brain damage that causes autism.

That wouldn't bother me (people can be as deluded as they want to be), *if* their delusions weren't hurting anyone. But the drastic rise in the cases of preventable childhood diseases (including deaths of children) that could have been prevented by vaccinations affects us all.

One unvaccinated kid doesn't hurt anyone, but when there are hundreds or thousands of them it starts to decrease our "herd immunity" to the point where we all become vulnerable. And that is unacceptable.

Jan 30, 2009
Since big pharma is behind, the question remains: who paid for this research? because we know that influences the outcome of the "investigation". We know that many children die every year when they are trying vaccines and new drugs. So don't play saints!

Jan 31, 2009
Pretty easy to post a link to the article. Not sure why the article doesn't have one. What's the point of the web if we don't use it?


Co-Author Paul A. Offit is a coinventor and patent coholder of the rotavirus vaccine Rotateq and has served on a scientific advisory board to Merck.

Jan 31, 2009
gopher65 if autism is genetic "only" then why has the incidence of a nearly non-existent disorder gone through the roof?

Vaccination does not prevent disease and it never has. All childhood diseases disappeared at the same rate according to improvements in nutrition and sanitation. We don't vaccinate for scarlet fever and guess went away just like everything else did.

And there is no such thing as herd immunity. If the vaccine protects individuals then it doesn't matter how many are vaccinated in a population. Only those who were not vaccinated would be effected. The fact that vaccinated children get the diseases they have supposedly been protected from and that outbreaks still occur is a pretty obvious indicator that vaccines don't perform as advertised.

You need to actually research the topic and follow the money. Oh, and try watching a bit less TV as well.

Jan 31, 2009
Why don't natural born Omish people get Autism? We do after all have a wonderfull control group in their mist.

Jan 31, 2009
mysticshakra: because 100 years ago people had 12 children, and 10 of them died before they hit 4 years old (because there were no dreaded vaccines and antibiotics). People seem to forget just how far we've come in a very short time.

Why does this matter to autism? Because autism was only recently identified as a separate illness. Before such people either died very young, or they were simply grouped together with the retards, fools, and village idiots.

And there is no such thing as herd immunity. If the vaccine protects individuals then it doesn't matter how many are vaccinated in a population.

That... that is one of the ignorant things I've ever read, even on the internet. Know why you've never caught Ebola? Because of geographic immunity, which is just a subtype of herd immunity.

I'll begin at the beginning, and I'll try and keep this short and I'll simply the concepts involved as much as possible. To save time and effort on my part, I'll do this with a simple series of facts, in the form of a numbered list:

1) Vaccines are not 100% effective.

2) For the sake of discussion, let's say that a particular vaccine that we're talking about is 80% effective (every type of vaccine is different).

3) In order to make this easier to understand, let's say that the disease that the vaccine is suppose to protect against is 100% contagious to a person who has never had the illness before, and that once you've had it, you can never catch it again. This means that if you come in contact with an infected person, you definitely get the disease.

4) So. You get the vaccine. The vaccine is 80% effective. This means that instead of having a 100% chance of catching the disease, you now have a 20% chance.

5) If everyone is unvaccinated, then every person in the country will eventually catch it. From New York to California, and everywhere in between.

6) If the whole population is vaccinated, then the disease only has a 20% chance of spreading to each new person it encounters. Eventually any infected person will be completely surrounded by people who are immune to the disease. So the illness won't have a chance to spread from that person to a new person.

7) Once that happens, the disease is effectively boxed up in one area. It can't spread, because people who are immune are acting like a firewall, blocking it from spreading.

8) Now lets say that there is one, ONE unvaccinated person in the whole country. He didn't get the vaccine cause he's really lazy. He lives in Florida. Since he is unvaccinated, he has a 100% chance of catching the illness if he comes in contact with an infected person. But the disease never spread past New York, so he never gets the opportunity to come in contact with an infected person, so he never becomes infected.

THAT is herd immunity.

Jan 31, 2009
*sighs* The edit function on this message board doesn't last *quite* long enough:P. Lots of misspellings and misused words in there (eg, simply instead of simplify).

I just wanted to add one thing:

Autism isn't a new disorder, it is just a newly recognized disorder. They still haven't even decided on precise diagnostic criteria (that means that they haven't decided what is "autism" and what is "mentally handicapped" and what is just a bad case of "antisocial behaviour").

The reason autism is more diagnosed in developed countries is cause, well, we're not dying by the HUNDREDS OF MILLIONS of Tuberculosis, Malaria, and Yellow Fever like they do in half of the developing countries. Frankly, if we were, no one would care about autistic kids. We'd have bigger fish to fry.

That's how it use to be here, and we didn't care about autistics. They were just one small set of "freaks", and we had other, more pressing, problems to diagnose and treat. Now we've cured all of the easy-to-cure illnesses, so we're naturally more worried about the ones that we haven't cured; the tough to cure ones. People use to worry about catching Leprosy, or Polio, or Smallpox, or Tuberculosis, or Syphilis (all very very very deadly diseases), but now we've cured or irradiated those. Now they care about things like cancer, HIV, Autism, and Alzheimer's, and a host other things that barely registered on their list of worries before (rashes, cataracts, etc).

People are never satisfied, are they;). If you went back in time and told people that in 100 years we'd have irradiated smallpox, they'd think that we didn't have a care in the world. Little would they know that we'd just decide that living healthily until we're 40 isn't good enough for us anymore, and now we want to live all the way to 120 cancer free. And that we'd decide that having 11 out of 12 of our children be healthy isn't good enough for us (instead of 2 out of 12 like they had), no, we want all 12 to be perfect. They'd probably think we were greedy:P. I say that they'd be wrong, but that's what they'd think.

Feb 01, 2009
The premise that supports the herd immunity theory is, of course, that the vaccine works, and offers years of protection.

But, at best, it works for some of the people some of the time %u2013 a fact that governments and health officials are loathe to reveal.

For instance, more than three-quarters of all measles cases in the UK that were diagnosed between 1985 and 1986 had been properly vaccinated. A similar pattern can be found in the USA. In one outbreak in 1986 in Corpus Christi, Texas, 99 per cent of affected children had been vaccinated. It%u2019s a picture that applies across the whole of the USA where 80 per cent of all cases of measles occur in vaccinated children.

Feb 01, 2009
The medical literature has a surprising number of studies documenting vaccine failure. Measles, mumps, small pox, pertussis, polio and Hib outbreaks have all occurred in vaccinated populations. , , , , In 1989 the CDC reported: "Among school-aged children, [measles] outbreaks have occurred in schools with vaccination levels of greater than 98 percent. [They] have occurred in all parts of the country, including areas that had not reported measles for years."

The CDC even reported a measles outbreak in a documented 100% vaccinated population. A study examining this phenomenon concluded, "The apparent paradox is that as measles immunization rates rise to high levels in a population, measles becomes a disease of immunized persons."

A more recent study found that measles vaccination "produces immune suppression which contributes to an increased susceptibility to other infections." These studies suggest that the goal of complete "immunization" may actually be counter-productive, a notion underscored by instances in which epidemics followed complete immunization of entire countries.

Japan experienced yearly increases in small pox following the introduction of compulsory vaccines in 1872. By 1892, there were 29,979 deaths, and all had been vaccinated.

In the early 1900's, the Philippines experienced their worst smallpox epidemic ever after 8 million people received 24.5 million vaccine doses (achieving a vaccination rate of 95%); the death rate quadrupled as a result.

Before England's first compulsory vaccination law in 1853, the largest two-year smallpox death rate was about 2,000; in 1870-71, England and Wales had over 23,000 smallpox deaths. In 1989, the country of Oman experienced a widespread polio outbreak six months after achieving complete vaccination.

In the US in 1986, 90% of 1300 pertussis cases in Kansas were "adequately vaccinated." 72% of pertussis cases in the 1993 Chicago outbreak were fully up to date with their vaccinations.

Feb 01, 2009
But, at best, it works for some of the people some of the time

Umm... yeah? The fact that vaccines aren't 100% effective is the reason that they cause herd immunity. That's why *herd immunity* exists, rather than *absolute immunity*, which is what would happen if the vaccine was 100% effective. Herd immunity is a result of the ineffectiveness of vaccines, not of their perfection.

Vaccines don't stop a disease outbreak from happening, they stop the disease from entering an exponential spread pattern (when an exponential spread pattern isn't stopped in time, a minor outbreak leads to an epidemic, or, rarely, a pandemic).

You really should read up on vaccines. You're "punching at strawmen", as it were, by claiming that they don't work 100% of the time. Of course they don't. They aren't suppose to, and no one, NO ONE, claims that they do.

I'm not saying any of this to be offensive. I'm really not. You're certainly not the only person I've met who wasn't read up on vaccines (most people aren't). One of the somewhat unfortunate things about our society is that we, as a society, now know so many things about so many topics that no single person can be fully educated on them all.

Feb 01, 2009
You're trying gopher65, and to an undergrad in microbiology, you make very good points. You also did a very good job explaining the points of contention.
Unfortunately, mysticshakra doesn't seem to understand that viruses and bacteria are CONSTANTLY evolving, and the vaccine needs to be updated as well. For some diseases, the rate of mutation is quite low, and a vaccine can be employed easily to destroy said disease... for others, not so much. Even if you did show me the citations for all the scary numbers you threw up there, I would point out that this is (mainly) back in the 1900s! If you honestly believe our vaccines haven't improved since then, you need to have your head examined. As for more recent outbreaks (like the 1986 one you claimed), I would say the virus has to win once in a while. It happens, and it sucks. Fortunately for you (and humanity) we DON'T have the numbers that say how many people would have died if the vaccine were not administered.
One more point... look at the geographic depiction of recent smallpox outbreaks in the 2000s. You'll find they are only where we are unable to administer the vaccine (ie: Warzones). Living all happily in the Americas, I have not been vaccinated for smallpox, and I don't mind. Why? Because of the incredible systems of herd immunity and geographic isolation, which have only been possible to achieve thanks to our vaccination programs.

My advice to you people who don't "believe" in vaccines: Get a degree in microbiology, then make the call. It's like explaining nuclear fission to monkeys if you don't have a good background in biology.

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